Astronomers Announce First Newborn Stars at Milky Way’s Core

Astronomers have found the first evidence of newborn stars at the center of the Milky Way, a region once thought to be inhospitable to the formation of new stars.

Solange Ramirez, the principal investigator of the research program at NASA’s Exoplanet Science Institute at Caltech, announced three objects during a press conference today as part of the 214th meeting of the American Astronomical Society meeting in Pasadena.

“These baby stars … are stars that have just ignited their core, and are just starting to produce light,” she said. “It is a very early phase.”

The discovery was made using the infrared vision of NASA’s Spitzer Space Telescope.

The heart of our spiral galaxy is cluttered with stars, dust, and gas, and at its very center, a supermassive black hole. Conditions there are harsh, with fierce stellar winds, powerful shock waves, and other factors that make it difficult for stars to form. Astronomers have known that stars can form in this chaotic place, but they’re baffled as to how this occurs. Confounding the problem is all the dust standing between us and center of our galaxy. Until now, nobody had
been able to definitively locate any baby stars.

“These stars are like needles in a haystack,” Ramirez said. “There’s no way to find them using optical light, because dust gets in the way. We needed Spitzer’s infrared instruments to cut through the dust and narrow in on the objects.”

Ramirez and her colleagues plan to look for additional baby stars in the future, and ultimately to piece together what types of conditions allow stars to form in such an inhospitable environment as our galaxy’s core.

“By studying individual stars in the galactic center, we can better understand how stars are formed in different interstellar environments,” said Deokkeun An, also of Caltech, who is lead author of a paper submitted for publication in the Astrophysical Journal.

“The Milky Way galaxy is just one of more than hundreds of billions of galaxies in the visible universe. However, our galaxy is so special because we can take a closer look at its individual stellar components.”

The core of the Milky Way is a mysterious place about 600 light-years across. While this is just a fraction of the size of entire the Milky Way, which is about 100,000 light-years across, the core is stuffed with 10 percent of all the gas in the galaxy — and loads of stars.

Before now, there were only a few clues that stars can form in the galaxy’s core. Astronomers had found clusters of massive adolescent stars, in addition to clouds of charged gas — a sign that new stars are beginning to ignite and ionize surrounding gas. Past attempts had been unsuccessful in finding newborn stars, or as astronomers call them, young stellar objects.

The astronomers looked at their candidate stars with Spitzer’s spectrograph — an instrument that breaks light apart to reveal its rainbow-like array of infrared colors. Molecules around stars leave imprints in their light, which the spectrograph can detect.

The results revealed three stars with clear signs of youth, for example certain warm, dense gases. These youthful features are found in other places in the galaxy where stars are being formed.

“It is amazing to me that we have found these stars,” said Ramirez. “The galactic center is a very interesting place. It has young stars, old stars, black holes, everything. We started mining a catalog of about one million sources and managed to find three young stars — stars that will help reveal the secrets at the core of the Milky Way.”

The young stellar objects are all less than about one million years old. They are embedded in cocoons of gas and dust, which will eventually flatten to disks that, according to theory, later lump together to form planets.

10 Responses

“…a region once thought to be inhospitable to the formation of new stars.”

“…other factors that make it difficult for stars to form…but they’re baffled as to how this occurs.”

Could it be that the environment at the core of the Milky Way is not as “modern” astronomers have assumed?

How could that be?

Maybe, the dyanamics are NOT controlled by “mechanical” fluid dynamics, such as “shock waves” and “winds” controlled by gravity, but rather is influenced by electromagnetic forces which are 10^39 order of magnitude stronger, yet still conducive to star formation.

Of course, one of the reasons that “the birth of stars” was considered difficult at the galactic core was because of the presence of a so-called “super massive black hole”, which theoretically would cause gravitational tides that would rip apart any incipient stars and prevent their formation.

Such that any stars that were present, was the result of gravitaional pull which drew already fully formed stars into the core region.

Apparently, such is not the case.

In other words, astonomers were “baffled” because their theories didn’t match the expected result.

Astronomers were “baffled” because their model didn’t predict “X”. (a variant of “surprised”).

How many times do we have to read some variant of the, above, before some people ease up and consider other alternative possibilities?

Isn’t that kind of what Science is about — considering all the possibilities?

Well it does seem rather funny that a 4 million solar mass plasmoid with a diameter less than Pluto’s orbit around the sun can manifest itself at the center of our galaxy and yet give off traces of barely detectable near infrared light accompanied by a variable radio and x-ray emission with periods of minutes to days. Exactly how does Plasma Cosmology account for these observations in the NIR, radio & x-ray portions of the EM spectrum, and in accordance to the already well-documented population of stars orbiting this mass in highly eccentric , high velocity orbits? Do you have any specifically relevant evidence (peer-reviewed papers) to back up any of you Plasma Cosmology assertions in regards to Sgr A* ? Just a yes or no answer will suffice.

“How many times do we have to read some variant of the, above, before some people ease up and consider other alternative possibilities?”

So you believe that we should just somehow ‘know’ the answers before we can even ask the questions? Honestly…

“Isn’t that kind of what Science is about — considering all the possibilities?”

I’d argue no – science is about considering possibilities that can be falsified, that have explanatory power and make testable predictions, and that can hold up under scrutiny when compared to observation. Ghosts are a possibility, but we don’t consider them to be a feasible proposition… I don’t anyway.

We don’t simply throw the baby out with the bathwater the moment we find something that is difficult to explain with our current theories. If something were IMPOSSIBLE to explain with a given theory, them that would be different. However, astronomy deals with such complex dynamics that even basic physical interactions can end up being utterly unpredictable. Do our current theories do an exceptional job? Damn straight they do. That is not to say they won’t be superseded or modified, but just because a few ill-understood processes can’t yet be fully incorporated into them yet is a preposterous reason to abandon them entirely.

An interesting overview paper was published last year (2008) by Don Figer entitled “Massive Star Formation in the Galactic Center”. A copy of this short, informative paper can be found here: http://www.cis.rit.edu/~dffpci/private/papers/stsci06/stsci06.pdf . Dr Figer specifically concentrates on the latest research on the Central Cluster of our Milky Way, the Arches Cluster and the Quintuplet Cluster (and its’ ‘Pistol Star’). MANY references are provided for all three massive clusters up to the date of publication (March 2008). Also included are useful diagrams highlighting these clusters and their positions and proximity to the center of our galaxy. And, of course, many painstakingly acquired images of these objects are also included. Interested readers would do well to check out the paper, as it reflects current research on these home grown massive stellar clusters and the bizarre neighborhood they inhabit.

A recent paper on the formation of massive stars near the galactic center appeared at the arXiv.org site for June 16th here :http://arxiv.org/abs/0906.2917 . Entitled “Star Formation at the Galactic Center”, the paper focuses on H.E.S.S. observations of 100 GeV gamma-rays from Westerlund 1 & 2 and Pismis 22. Definitely an active star forming region even in this extreme region near the Galactic Center.